Incidence, Risk Factors, and Outcomes Associated With Permanent Pacemaker Implantation Following Tricuspid Valve Surgery.

BACKGROUND: Data regarding permanent pacemaker (PPM) implantation following tricuspid valve surgery (TVS) are limited. We sought to evaluate its incidence, risk factors, and outcomes. METHODS AND RESULTS: Medicare beneficiaries who underwent TVS from 2013 to 2020 were identified. Patients who underwent TVS for endocarditis were excluded. The primary exposure of interest was new PPM after TVS. Outcomes included all-cause mortality and readmission with endocarditis or heart failure on follow-up. Among the 13 294 patients who underwent TVS, 2518 (18.9%) required PPM placement. Risk factors included female sex (relative risk [RR], 1.26 [95% CI, 1.17-1.36], P<0.0001), prior sternotomy (RR, 1.12 [95% CI, 1.02-1.23], P=0.02), preoperative second-degree heart block (RR, 2.20 [95% CI, 1.81-2.69], P<0.0001), right bundle-branch block (RR, 1.21 [95% CI, 1.03-1.41], P=0.019), bifascicular block (RR, 1.43 [95% CI, 1.06-1.93], P=0.02), and prior malignancy (RR, 1.23 [95% CI, 1.01-1.49], P=0.04). Tricuspid valve (TV) replacement was associated with a significantly higher risk of PPM implantation when compared with TV repair (RR, 3.20 [95% CI, 2.16-4.75], P<0.0001). After a median follow-up of 3.1 years, mortality was not different in patients who received PPM compared with patients who did not (hazard ratio [HR], 1.02 [95% CI, 0.93-1.12], P=0.7). PPM placement was not associated with a higher risk of endocarditis but was associated with a higher risk of heart failure readmission (HR, 1.28 [95% CI, 1.14-1.43], P<0.001). CONCLUSIONS: PPM implantation frequently occurs after TVS, notably in female patients and patients undergoing TV replacement. Although mortality is not increased, it is associated with higher rates of heart failure rehospitalization.

Outcomes of patients implanted with an atrioventricular synchronous leadless ventricular pacemaker in the Medicare population.

BACKGROUND: The Micra AV Coverage with Evidence Development study is a novel analysis of utilization and outcomes associated with Micra AV leadless pacing in US Medicare patients. OBJECTIVE: The purpose of this study was to describe patient characteristics, complications, and outcomes of patients implanted with a Micra AV leadless pacemaker compared with a contemporaneous cohort of patients implanted with a dual chamber transvenous pacemaker. METHODS: Patients implanted with Micra AV (n = 7471) or a dual chamber transvenous pacemaker (n = 107,800) from February 5, 2020, through December 1, 2021, were identified using device registry-linked Medicare claims data. Acute complications were assessed at 30 days, and chronic complications, reinterventions, and all-cause mortality were assessed at 6 months. RESULTS: Patients implanted with Micra AV had higher rates of end-stage renal disease (14.9% vs 2.0%; P < .0001) and overall comorbidity burden (mean Charlson Comorbidity Index 4.9 vs 3.8; P < .0001). There was no difference in the unadjusted rate of complications at 30 days (9.1% vs 8.7%; P = .61), and patients implanted with Micra AV had a significantly lower adjusted rate of complications (8.6% vs 11.0%; P < .0001). At 6 months, patients implanted with Micra AV had significantly lower rates of complications (adjusted hazard ratio 0.50; 95% confidence interval 0.43-0.57; P < .0001) and reinterventions (adjusted hazard ratio 0.46; 95% confidence interval 0.36-0.58; P < .0001). Patients implanted with Micra AV had higher all-cause mortality at 30 days and 6 months, likely because of differences in the underlying risk of mortality. CONCLUSION: Patients implanted with Micra AV had similar rates of complications at 30 days and significantly lower rates of complications and reinterventions at 6 months, despite being sicker than patients implanted with a transvenous pacemaker.

Pacing-induced cardiomyopathy: A systematic review and meta-analysis of definition, prevalence, risk factors, and management.

Pacing-induced cardiomyopathy is a potential complication of right ventricular pacing. Definition varies between studies and the optimal management approach is uncertain. We aimed to characterize definition, prevalence, risk factors, and treatment strategies of pacing-induced cardiomyopathy (PiCM). We performed a systematic review and meta-analysis of studies that evaluated PiCM after pacemaker implantation identified through a literature search of PubMed and EMBASE up to March 2022. We collected data on the study definition of PiCM and calculated pooled prevalence across studies. Meta-analysis with random effects modeling was used to assess the association between potential risk factors and PiCM, reported as odds ratio with 95% confidence interval. Twenty-six studies (6 prospective studies) with a total of 57,993 patients (mean/median age range was 51-78 years; female 45%) were included in the final analysis. Fifteen unique definitions of PiCM were reported. The pooled prevalence of PiCM was 12% (95% confidence interval 11%-14%). In meta-analysis, risk factors included male sex, history of myocardial infarction, chronic kidney disease, atrial fibrillation, baseline left ventricular ejection fraction, native QRS duration, right ventricular pacing percentage, and paced QRS duration. Treatment strategies identified included biventricular cardiac resynchronization therapy (6 studies) and His-bundle pacing (3 studies). Definition of PiCM varied significantly between studies. More than 1 in 10 patients with chronic right ventricular pacing developed PiCM. Key risk factors included baseline left ventricular ejection fraction, native QRS duration, RV pacing percentage, and paced QRS duration. The optimal management strategy has yet to be defined. Further research is needed to define and treat this understated complication.

Epidemiology, evaluation, and management of conduction disturbances after transcatheter aortic valve replacement.

Aortic stenosis is the most common valvulopathy requiring replacement by means of the surgical or transcatheter approach. Transcatheter aortic valve replacement (TAVR) has quickly become a viable and often preferred treatment strategy compared to surgical aortic valve replacement. However, transcatheter heart valve system deployment not infrequently injures the specialized electrical system of the heart, leading to new conduction disorders including high-grade atrioventricular block and complete heart block (CHB) necessitating permanent pacemaker implantation (PPI), which may lead to deleterious effects on cardiac function and patient outcomes. Additional conduction disturbances (e.g., new-onset persistent left bundle branch block, PR/QRS prolongation, and transient CHB) currently lack clearly defined management algorithms leading to variable strategies among institutions. This article outlines the current understanding of the pathophysiology, patient and procedural risk factors, means for further risk stratification and monitoring of patients without a clear indication for PPI, our institutional approach, and future directions in the management and evaluation of post-TAVR conduction disturbances.

Left Ventricular Rapid Pacing Via the Valve Delivery Guidewire in Transcatheter Aortic Valve Replacement.

OBJECTIVES: This study investigated whether left ventricular (LV) stimulation via a guidewire-reduced procedure duration while maintaining efficacy and safety compared with standard right ventricular (RV) stimulation. BACKGROUND: Rapid ventricular pacing is necessary to ensure cardiac standstill during transcatheter aortic valve replacement (TAVR). METHODS: This is a prospective, multicenter, single-blinded, superiority, randomized controlled trial. Patients undergoing transfemoral TAVR with a SAPIEN valve (Edwards Lifesciences, Irvine, California) were allocated to LV or RV stimulation. The primary endpoint was procedure duration. Secondary endpoints included efficacy, safety, and cost at 30 days. RESULTS: Between May 2017 and May 2018, 307 patients were randomized, but 4 were excluded because they did not receive the intended treatment: 303 patients were analyzed in the LV (n = 151) or RV (n = 152) stimulation groups. Mean procedure duration was significantly shorter in the LV stimulation group (48.4 ± 16.9 min vs. 55.6 ± 26.9 min; p = 0.0013), with a difference of -0.12 (95% confidence interval: -0.20 to -0.05) in the log-transformed procedure duration (p = 0.0012). Effective stimulation was similar in the LV and RV stimulation groups: 124 (84.9%) versus 128 (87.1%) (p = 0.60). Safety of stimulation was also similar in the LV and RV stimulation groups: procedural success occurred in 151 (100%) versus 151 (99.3%) patients (p = 0.99); 30-day MACE-TAVR (major adverse cardiovascular event-transcatheter aortic valve replacement) occurred in 21 (13.9%) versus 26 (17.1%) patients (p = 0.44); fluoroscopy time (min) was lower in the LV stimulation group (13.48 ± 5.98 vs. 14.60 ± 5.59; p = 0.02), as was cost (€18,807 ± 1,318 vs. €19,437 ± 2,318; p = 0.001). CONCLUSIONS: Compared with RV stimulation, LV stimulation during TAVR was associated with significantly reduced procedure duration, fluoroscopy time, and cost, with similar efficacy and safety. (Direct Left Ventricular Rapid Pacing Via the Valve Delivery Guide-wire in TAVR [EASY TAVI]; NCT02781896).

Infections and associated costs following cardiovascular implantable electronic device implantations: a nationwide cohort study.

Aims: This study assessed the contemporary occurrence of cardiac device infections (CDIs) following implantation in French hospitals and estimated associated costs. Methods and Results: A retrospective analysis was conducted on the French National Hospital Database (PMSI). Patients with a record of de novo cardiac implantable electronic device (CIED) implantation or replacement interventions in France in 2012 were identified and followed until the end of 2015. Cardiac device infections (CDIs) were identified based on coding using the French classification for procedures [Classification Commune des Actes Médicaux (CCAM)] and International Classification of Diseases (ICD-10). Associated costs were estimated based on direct costs from the perspective of the French social security system. In total 78 267 CIED patients (72% de novo implants) were identified (15% defibrillators; 84% pacemakers). The 36-month infection rate associated with de novo defibrillator-only implants, as well as for cardiac resynchronisation therapy - defibrillators (CRT-Ds) was 1.6%. The CDI risk was 2.9% and 3.9% for replacement ICDs and CRT-Ds. Infection rates were lower for de novo single-chamber pacemaker (SCP)/dual-chamber pacemaker (DCP) (0.5%) and cardiac resynchronisation therapy - pacemaker (CRT-P) implants (1.0%), while for replacement procedures the risk increased to 1.4% (SCP/DCP) and 1.3% (CRT-P). Mean infection-related costs over 24 months were €20 623 and €23 234 for CDIs associated with replacement and de novo procedures, and overall costs were not significantly different between pacemaker and defibrillator patients. Conclusion: Cardiac device infections in France are associated with substantial costs, when considering inpatient hospitalizations. Strategies to minimize the rate of CIED infection should be a priority for health care providers and payers.

Atrio-ventricular junction ablation and pacemaker treatment: a comparison between men and women.

OBJECTIVES: To explore sex differences regarding indication for atrio-ventricular junction ablation (AVJ), choice of pacing system, complications to pacemaker treatment, long-term outcome, and cause of death after AVJ ablation. DESIGN: 700 patients who had undergone AVJ ablation between January 1990 and December 2010 were included. Data were retrieved from the patients´ medical records and the Swedish Pacemaker and Implantable Cardioverter-Defibrillator Registry. Information about admission to hospital and cause of death was retrieved from the National Board of Health and Welfare. RESULTS: Mean follow-up was 90 ± 64 months. Indication for AVJ ablation, choice of pacing system, and outcome after AVJ ablation differed between the sexes. The men had more often permanent atrial fibrillation, p = .0001, and a VVIR pacemaker or cardiac resynchronization therapy (CRT) implanted prior to ablation, p = .0001. Heart failure was present in 44% of the men vs. 28% of the women, p = .0001. LVEF decreased slightly in the whole cohort after the AVJ ablation. There were no sex differences in complication rates due to the pacemaker/ICD treatment, p = .3 or mortality due to AVJ ablation. CONCLUSION: In this long-term follow-up in patients with atrial fibrillation treated with AVJ ablation and pacing, indication, choice of pacing system, and morbidity differed but there were no sex differences regarding survival or primary cause of death found. The main factor influencing survival was age at the time of ablation. Women less often received treatment with ICD and/or CRT when indication was present compared with men.

Incidence of arrhythmias and impact of permanent pacemaker implantation in hospitalizations with transcatheter aortic valve replacement.

BACKGROUND: This study sought to analyze in-hospital outcomes associated with preexisting and newly implanted permanent pacemaker (PPM) in patients who underwent transcatheter aortic valve replacement (TAVR). PPM implantation following the development of conduction abnormalities is a common adverse event following TAVR. Furthermore, PPM implantation rates are higher in TAVR hospitalizations compared with the surgical alternative, thus we have analyzed the predictors of pacing post-TAVR. HYPOTHESIS: We hypothesize that incidence of arrhythmias are high post-TAVR and have worse adverse outcomes after receiving PPM. METHODS: The study population was identified from the National Inpatient Sample database between 2012 and 2014. TAVR population was identified using ICD-9-CM procedure codes 35.05 and 35.06. Hospitalizations were divided into 3 group: (1) with preexisting PPM, (2) with newly implanted PPM, and (3) without any PPM. RESULTS: Overall, 0.8% of hospitalizations presented with preexisting PPM and 23.7% of hospitalizations received new PPM. The overall incidence of atrial fibrillation was 44.5%, left bundle branch block 8.9%, complete atrioventricular block 9.5%, and right bundle branch block 2.7%. In-hospital mortality was higher in hospitalizations receiving PPM compared with those without (4.9% vs 4.0%; P = 0.05). Length of stay and cost were higher in the group receiving new PPM. Female sex, atrial fibrillation, left bundle branch block, and second-degree and complete atrioventricular block were significant predictors for receiving PPM after TAVR. CONCLUSIONS: A risk stratification for hospitalizations with conduction disorders is necessary to avoid longer hospital stays, added costs, and mortality. Further research is warranted to investigate additional predictors for PPM after TAVR.

Increased healthcare utilization associated with complete atrioventricular block in pacemaker patients.

PURPOSE: The purpose of the current study is to characterize and quantify the impact of complete atrioventricular block (cAVB) on heart failure hospitalization (HFH) and healthcare utilization in pacemaker (PM) patients. METHODS: Patients ≥ 18 years implanted with a dual-chamber PM from April 2008 to March 2014 were selected from the MarketScan® Commercial and Medicare Supplemental claims databases. Patients with ≤ 1-year continuous MarketScan enrollment prior to and post-implant, and those with prior HF diagnosis were excluded. Patients were dichotomized into those with cAVB, defined as a 3rd degree AVB diagnosis or AV node ablation in the year prior to PM implant, versus those without any AVB (noAVB). Post-implant HFH and associated costs were compared based on inpatient claims. RESULTS: The study cohort included 21,202 patients, of which 14,208 had no AVB and 6994 had cAVB, followed for 2.39 and 2.27 years, respectively. Patients with cAVB were associated with a significantly increased risk of cumulative HFH (HR 1.59 [95% CI 1.35-1.86] p < 0.001) and significantly higher costs ($636 [609-697] vs $369 [353-405] per pt-year, p < 0.001) compared to those with no AVB. CONCLUSIONS: Among dual-chamber PM patients without prior HF, cAVB is associated with a significantly increased risk of HFH and greater HF-related healthcare utilization. Identifying patients at high risk for HF in the setting of RV pacing, and potentially earlier use of biventricular or selective conduction system pacing, may reduce HF-related healthcare utilization.

Survival in Women Versus Men Following Implantation of Pacemakers, Defibrillators, and Cardiac Resynchronization Therapy Devices in a Large, Nationwide Cohort.

BACKGROUND: Whether outcomes differ between sexes following treatment with pacemakers (PM), implantable cardioverter defibrillators, and cardiac resynchronization therapy (CRT) devices is unclear. METHODS AND RESULTS: Consecutive US patients with newly implanted PM, implantable cardioverter defibrillators, and CRT devices from a large remote monitoring database between 2008 and 2011 were included in this observational cohort study. Sex-specific all-cause survival postimplant was compared within each device type using a multivariable Cox proportional hazards model, stratified on age and adjusted for remote monitoring utilization and ZIP-based socioeconomic variables. A total of 269 471 patients were assessed over a median 2.9 [interquartile range, 2.2, 3.6] years. Unadjusted mortality rates (MR; deaths/100 000 patient-years) were similar between women versus men receiving PMs (n=115 076, 55% male; MR 4193 versus MR 4256, respectively; adjusted hazard ratio, 0.87; 95% CI, 0.84-0.90; P<0.001) and implantable cardioverter defibrillators (n=85 014, 74% male; MR 4417 versus MR 4479, respectively; adjusted hazard ratio, 0.98; 95% CI, 0.93-1.02; P=0.244). In contrast, survival was superior in women receiving CRT defibrillators (n=61 475, 72% male; MR 5270 versus male MR 7175; adjusted hazard ratio, 0.73; 95% CI, 0.70-0.76; P<0.001) and also CRT pacemakers (n=7906, 57% male; MR 5383 versus male MR 7625, adjusted hazard ratio, 0.69; 95% CI, 0.61-0.78; P<0.001). This relative difference increased with time. These results were unaffected by age or remote monitoring utilization. CONCLUSIONS: Women accounted for less than 30% of high-voltage implants and fewer than half of low-voltage implants in a large, nation-wide cohort. Survival for women and men receiving implantable cardioverter defibrillators and PMs was similar, but dramatically greater for women receiving both defibrillator- and PM-based CRT.

Assessment of the Extravascular Implantable Defibrillator: Feasibility of Substernal Ventricular Pacing.

INTRODUCTION: The objective of this study was to assess feasibility of ventricular pacing and thresholds from within the substernal space to examine a new extravascular ICD configuration with pacing capabilities. METHODS: In patients undergoing midline sternotomy, a duodecapolar diagnostic pacing catheter was positioned in the substernal space anterior to the pericardium, and a cutaneous patch in left lateral position. Different unipolar and bipolar pacing configurations were assessed. Strength-duration curves were performed to identify the optimal output, starting at 25 mA with a pulse width of 10 milliseconds. RESULTS: Eight patients with mean age 69 ± 9 years were included. In 5, ventricular capture was achieved in ≥1 configuration. The mean bipolar pacing thresholds at PW 10, 5, 3, 1 milliseconds were 12.4 ± 3.7 mA (5 patients), 13.3 ± 5.8 mA (3 patients), 18.3 ± 5.7 mA (3 patients), and 25 ± 0 mA (2 patients), respectively. The 60-mm electrode spacing was the most successful bipolar configuration. Unipolar pacing was successful in 3 out of 4 patients with mean thresholds of 10 ± 0 mA at 10 milliseconds (3 patients), 15 ± 0 mA at 5 milliseconds (3 patients), 16.7 ± 2.9 mA at 3 milliseconds (3 patients), and 20 ± 7.1 mA at 1 milliseconds (2 patients). CONCLUSION: Ventricular pacing from the substernal space in patients with midline sternotomy is feasible. Closed sternum studies are needed to determine pacing thresholds more accurately.

Project My Heart Your Heart: An Idea Whose Time Has Come.

It is estimated that nearly 1 million patients in low-income countries die every year from bradyarrhythmias coupled with no access to a pacemaker. At the same time, it is estimated that tens of thousands of used devices could be harvested from hospitals, funeral homes, and crematories in wealthy nations if such a practice was legal and proven to be safe and efficacious. Project My Heart Your Heart is a collaborative, multinational effort with a goal of making pacemaker recycling a reality. Since its inception 4 years ago, the project has studied beliefs and attitudes of this idea among patients, pacemaker recipients, funeral home directors, and arrhythmia specialists. The project has explored the safety and efficacy of this practice in several small pilot studies. Nearly 15,000 used devices have been received and evaluated. Efforts to fully define optimal methods for sterilization and device processing have progressed positively. Safe, effective pacemaker recycling is possible and is generally supported by the public, patients, and cardiovascular specialists. An ongoing dialogue with the FDA will hopefully lead to a large pivotal study in five countries which will definitively establish this practice including optimal strategies for device removal, interrogation, sterilization, handling, implantation, and follow-up at charitable pacemaker facilities servicing low income patients throughout the world.

Association between hospital procedure volume and early complications after pacemaker implantation: results from a large, unselected, contemporary cohort of the German nationwide obligatory external quality assurance programme.

AIMS: Several studies demonstrated an inverse relationship between cardioverter-defibrillator implantation volume and complication rates, suggesting better outcomes for higher volume centres. However, the association of institutional procedural volume with patient outcomes for permanent pacemaker (PPM) implantation remains less known, especially in decentralized implantation systems. METHODS AND RESULTS: We performed retrospective examination of data on patients undergoing PPM from the German obligatory quality assurance programme (2007-12) to evaluate the relationship of hospital PPM volume (categorized into quintiles of their mean annual volume) with risk-adjusted in-hospital surgical complications (composite of pneumothorax, haemothorax, pericardial effusion, or pocket haematoma, all requiring intervention, or device infection) and pacemaker lead dislocation. Overall 430 416 PPM implantations were documented in 1226 hospitals. Systems included dual (72.8%) and single (25.8%) chamber PPM and cardiac resynchronization therapy (CRT) devices (1.1%). Complications included surgical (0.92%), and ventricular (0.99%), and atrial (1.22%) lead dislocation. Despite an increase in relatively complex procedures (dual chamber, CRT), there was a significant decrease in the procedural and fluoroscopy times and complications from lowest to highest implantation volume quintiles (P for trend <0.0001). The greatest difference was observed between the lowest (1-50 implantations/year-reference group) and the second-lowest (51-90 implantations/year) quintile: surgical complications [odds ratio (OR) 0.69; confidence interval (CI) 0.60-0.78], atrial lead dislocations (OR 0.69; CI 0.59-0.80), and ventricular lead dislocations (OR 0.73; CI 0.63-0.84). CONCLUSIONS: Hospital annual PPM volume was directly related to indication-based implantation of relatively more complex PPM and yet inversely with procedural times and rates of early surgical complications and lead dislocations. Thus, our data suggest better performance and lower complications with increasing procedural volume.

Atrial antitachycardia pacing and managed ventricular pacing in bradycardia patients with paroxysmal or persistent atrial tachyarrhythmias: the MINERVA randomized multicentre international trial.

AIMS: Atrial fibrillation (AF) is a common comorbidity in bradycardia patients. Advanced pacemakers feature atrial preventive pacing and atrial antitachycardia pacing (DDDRP) and managed ventricular pacing (MVP), which minimizes unnecessary right ventricular pacing. We evaluated whether DDDRP and MVP might reduce mortality, morbidity, or progression to permanent AF when compared with standard dual-chamber pacing (Control DDDR). METHODS AND RESULTS: In a randomized, parallel, single-blind, multi-centre trial we enrolled 1300 patients with bradycardia and previous atrial tachyarrhythmias, in whom a DDDRP pacemaker had recently been implanted. History of permanent AF and third-degree atrioventricular block were exclusion criteria. After a 1-month run-in period, 1166 eligible patients, aged 74 ± 9 years, 50% females, were randomized to Control DDDR, DDDRP + MVP, or MVP. Analysis was intention-to-treat. The primary outcome, i.e. the 2-year incidence of a combined endpoint composed of death, cardiovascular hospitalizations, or permanent AF, occurred in 102/385 (26.5%) Control DDDR patients, in 76/383 (19.8%) DDDRP + MVP patients [hazard ratio (HR) = 0.74, 95% confidence interval 0.55-0.99, P = 0.04 vs. Control DDDR] and in 85/398 (21.4%) MVP patients (HR = 0.89, 95% confidence interval 0.77-1.03, P = 0.125 vs. Control DDDR). When compared with Control DDDR, DDDRP + MVP reduced the risk for AF longer than 1 day (HR = 0.66, 95% CI 0.52-0.85, P < 0.001), AF longer than 7 days (HR = 0.52, 95% CI 0.36-0.73, P < 0.001), and permanent AF (HR = 0.39, 95% CI 0.21-0.75, P = 0.004). CONCLUSION: In patients with bradycardia and atrial tachyarrhythmias, DDDRP + MVP is superior to standard dual-chamber pacing. The primary endpoint was significantly lowered through the reduction of the progression of atrial tachyarrhythmias to permanent AF. CLINICALTRIALSGOV IDENTIFIER: NCT00262119.

Outcomes associated with warfarin use in older patients with heart failure and atrial fibrillation and a cardiovascular implantable electronic device: findings from the ADHERE registry linked to Medicare claims.

BACKGROUND: Warfarin use and associated outcomes in patients with heart failure and atrial fibrillation and a cardiovascular implantable electronic device have not been described previously. HYPOTHESIS: We hypothesized that warfarin is underused and is associated with lower risks of mortality, thromboembolic events, and myocardial infarction. METHODS: Using data from a clinical registry linked with Medicare claims, we examined warfarin use at discharge and 30-day and 1-year Kaplan-Meier estimates of all-cause mortality and cumulative incidence rates of mortality, thromboembolic events, myocardial infarction, and bleeding events in patients 65 years or older, with a history of atrial fibrillation and a cardiovascular implantable electronic device admitted with heart failure between 2001 and 2006, who were naïve to anticoagulation therapy at admission. We compared outcomes between patients who were or were not prescribed warfarin at discharge and tested associations between treatment and outcomes. RESULTS: Of 2586 eligible patients in 252 hospitals, 2049 were discharged without a prescription for warfarin. At 1 year, the group discharged without warfarin had a higher mortality rate after discharge (37.4% vs 28.8%; P < 0.001) but similar rates of thromboembolism, myocardial infarction, and bleeding events. After adjustment, treatment with warfarin was associated with lower risk of all-cause death 1 year after discharge (hazard ratio: 0.76, 95% confidence interval: 0.63-0.92). CONCLUSIONS: Among older patients with heart failure and atrial fibrillation and a cardiovascular implantable electronic device, 4 of 5 were discharged without a prescription for warfarin. Warfarin nonuse was associated with a higher risk of death 1 year after discharge. Clin. Cardiol. 2011 DOI: 10.1002/clc.22064 Damon M. Seils, MA, Duke University, assisted with manuscript preparation. Mr. Seils did not receive compensation for his assistance apart from his employment at the institution where the study was conducted. This study was supported by a research agreement between Duke University and Janssen Pharmaceuticals. The authors have no other funding, financial relationships, or conflicts of interest to disclose.

Device therapy in patients with heart failure and advanced age: too much too late?

Expanding indications for implantable cardiac rhythm devices coupled with the aging of the population have led to a progressive rise in the number of elderly patients referred for device implantation. However, the value of implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy (CRT) in elderly patients remains unproven, in part because few patients over 75 years of age were enrolled in the major device trials. In this article, we summarize the current evidence base regarding the use of device therapy in elderly heart failure patients. We review the efficacy, complications, indications, cost, and current controversies surrounding the use of ICDs and CRT in the geriatric age group. We conclude that reduced benefit coupled with higher complication rates and associated higher costs make it unlikely that the net clinical benefit of an ICD is favorable in most patients over 75 to 80 years of age. Conversely, preliminary data indicate that elderly patients undergoing CRT experience improved quality of life at acceptable cost, suggesting that CRT may be an attractive therapeutic option in appropriately selected patients of advanced age.

Assessment of left ventricular dyssynchrony in pacing-induced left bundle branch block compared with intrinsic left bundle branch block.

AIMS: Although electrocardiographic and echocardiographic findings with right ventricular (RV) pacing mimic intrinsic left bundle branch block (LBBB), left ventricular (LV) mechanical activation pattern may differ. We compared mechanical activation pattern of the LV in RV-pacing-induced LBBB with intrinsic LBBB in symptomatic chronic heart failure patients. METHODS AND RESULTS: We studied 37 patients with chronic RV-pacing and 37 patients with intrinsic LBBB who were referred for cardiac resynchronization therapy. Echocardiographic study including 2D speckle tracking longitudinal strain and M-mode were performed at baseline. Patients with intrinsic LBBB were younger, had higher prevalence of ischaemic heart disease, and had more severe depressed LV function. The basal-septal segments were the earliest activated sites in 11% of patients in RV-pacing-induced LBBB compared with 30% in intrinsic LBBB (P= 0.04). The mid- and basal-lateral segments were the latest activated sites in 57% of patients in RV-pacing-induced LBBB compared with 30% in intrinsic LBBB (P = 0.03). Left ventricular dyssynchrony, using longitudinal strain, time delay ≥ 130 ms between either mid-septal or apico-septal and either basal or mid-lateral segments was present in 71% of patients with RV-pacing-induced LBBB compared with 59% in intrinsic LBBB (P = 0.03). Using M-mode, LV dyssynchrony was present in 11% of patients with RV-pacing-induced LBBB compared with 59% in intrinsic LBBB (P = 0.02). CONCLUSION: Right ventricular-pacing results in less early basal activation and more often early mid-septal and late lateral wall activation in comparison with intrinsic LBBB. Imaging techniques that only visualize the basal- or mid-part of the LV may result in a serious underestimation of dyssynchrony in patients with pacing-induced LBBB.